Chronometric circuit controller



25, 1951 G. G. ENSIGN ETAL 2,579,914

CHRONOMETRIC CIRCUIT CONTROLLER Filed Dec. 9, 1949 2 SHEETSSHEET 2 FieA-H W ,i; 82 23 25 28 Geor eG.Ensign 40 8O Robs-t C.Hoppe d, GlennRSopar,IPVW

attorneys Patented Dec. 25, 1951 CHRONOMETRIC CIRCUIT CONTROLLER GeorgeG. Ensign, Robert C. Hoppe, and Glenn T. Soper, Elgin, Ill., assignorsto Elgin National Watch Company, Elgin, 111., a corporation of IllinoisApplication December 9, 1949, Serial No. 132,042

Claims. I

This invention relates to a chronometric circuit controller in which ahorological movement, driven from a source of power such as a mainspringand including a gear train whose movement is controlled by abalance-and-escape system, is employed for accomplishing the closing andopening of an electrical circuit successively at predetermined timeintervals.

A feature of the invention is the provision of a small, light, andcompact chronometric circuit controller, of small weight and capable ofcheap construction by the employment of normal parts of a standard watchmovement, with the addition or modification of minor parts for thecircuitbreaking and connection elements.

Another feature of the invention is the provision of a chronometriccircuit controller employing a standard watch movement modified by theseparation electrically fromthe main frame structures, of parts of thebalance-and-escape system whereby the already-occurring mechanicalcontacts in said systems, as an incident of the operation thereof, areemployed for making breaking an electrical circuit.

A further feature of the invention is the provision of a chronometriccircuit controller employing a normal watch movement modified by theemployment of an insulated part for the regulator lever and carrying atleast one regulator pin,

whereby an electrical circuit is made and broken 0 by the expanding andcontractin motion of the hair-spring during oscillation, wherewith thehairspring makes contact with said regulator pin.

Another feature of the invention is a modified form of constructionwherein a chronometric circuit controller comprises a normal watchmovement having jewel bearings for the balance assembly, this assemblybeing electrically isolated from the main frame, and employing aconductive roller pin for engaging the conductive pallet or escapementpiece, and with preference of emp103 nent of a conductive supportbearing for the arbor of said pallet or escapement piece, whereby tocomplete a short path to the main frame of the movement.

' A further feature is the provision of a chronometric circuitcontroller in a form in which a normal watch movement i modified to havethe balance support, such as the balance cock, insulated from the mainframe or pillar plate and in which the bearing for the balance staff,provided in the balance cock, is of conductive material to provide apart of an electrical circuit by which a conductive roller pin makesintermittent contact with the pallet or escape piece during the courseof oscillation: and preferably with a conductive support bearing for thepallet or escape piece arbor to provide a short path to the main frame.

With these and other features as objects in view, illustrative forms ofpractice of the invention are shown on the accompanying drawings, inwhich:

Figure 1 is a rear view of a normal watch movement, modified inaccordance with one form of practice of this invention, and having aconventionalized external electrical circuit connected therewith.

Figure 2 is an upright sectional view substantially on the plane 22represented on Figure 1, showing parts of the circuit controller on alarger scale.

Figure 3 is an exploded perspective view, showing the parts of theregulator assembly as modified for this first form of the invention.

Figure 4 i a View corresponding to Figure 2, but showing a modified formof construction of the parts.

Figure 5 is a fragmentary perspective view, substantially on the scaleof Figure 4, showing a method of insulating the balance cock and ofconnecting wires to establish external conductors.

Figure 6 is an elevation of a pallet for use in the structures, andindicating a position of the roller pin.

Figure '7 shows a further modification, shown as applied to parts of thestructure in Figure 4.

In these several forms of construction, a standard watch movement hasbeen illustrated as being modified for the ur o e of forming thechronometric circuit controller.

In Figure l the watch movement is shown in rear elevation, and it willbe understood that this movement includes the various parts such asmainspring, gear train, and the like, present in the normal watchmovement. In this rear elevation, the main front or pillar plate iii isconnected to the other parts, such as a bridge H on which are mountedthe wheels !2, I 3 of the winding train leading to the mainspring arborl3a, and the retaining pawl iii of this winding train, which holds themainspring in wound condition. Likewise, the pillar plate In supportsthe balance cock '5.

As shown in Figure 2, the pillar plate to and the balance cock [5receive the hole-stones i8, l', and the end-stones I8, l9 which are ofsapphire and of normal form and supported in a normal fashion. Thebalance staff 20 oscillates in these bearings. The balance staffsupports the balance wheel 2| and the roller 22 having the illustratedroller pin 23 for engaging in the fork of the pallet or escape piece 24.The staff 20 also supports the collet 25 to which is attached the innerend of the hairspring 2B. This hairspring includes an over-coil 21 atits outer end, which is raised above the general plane of the spirallycoiled art of the hairspring 23, and is passed into the hairspring stud28 and pinned thereto in the usual fashion (not shown), with thishairspring stud 28 fastened to the balance cock I as usual. These partsare normal and the standard watch movement can be employed therefor.

Likewise, the over-coil portion 21 of the hairspring alternately engagesthe inner regulator pin 30 and, the outer regulator pin 3| during itsoscillation, these pins being carried by the usual radial projection orear 32 of the regulator lever. One modification for forming the deviceas a chronometric circuit controller is to form this regulator lever intwo parts, as shown in Figure 3. The lower part 35 has an index arm 33of the usual length, but does not have an ear or radial projection forsupporting regulator pins: it can be made from a normal regulator leverby removing this car therefrom. The upper part 31 of the regulator leverhas a shortened index arm 38, and is provided with the usual car 32 forthe regulator pins 30, 3| which can be formed as usual with a frictionfit in the ear 32. An electrical conductor leading to the exterior ofthe movement includes a wire pig-tail 40 which is attached by a screw orby soldering 4| to the clipped index arm 38. During the preparation jand assembly of the parts of the regulator lever,

the lower surface of the upper part 31 and the upper surface of thelower part 35 are coated with an adhesive insulating cement, such as aphenol-aldehyde semi-cured resin: they are then pressed together with athin insulating sheet 42, such as cellophane, between them, and the unitis heated in an oven to about 150 C. for an hour to cure the cement toinsoluble and firmly adherent condition. trimmed as indicated by thedotted lines 43. The assembly can then be frictionally mounted upon thebalance, cock dome in the usual fashion, wherewith the insulating layer42 holds the regulator part 31 spaced and elevated out of electricalcontact with the balance cock dome 44.

The balance cock I5 is normally secured to the pillar plate by a screw46, and a further conductor A! may be connected beneath this screw toestablish electrical connection to the balance cock, as the frame andbalance cock are electrically connected and at the same potential.

The external circuit, for illustrative employment of the chronometriccircuit controller as a part of a system in which a battery current ismade and broken periodically through a transformer, is shown by Figure 1to have an extension of the conductor 40 to the positive pole of abattery 50, then through the primary winding 5| of the transformen'andback by the conductor ll to the balance cock. That is, it is preferredthat the positive pole of the battery be connected to the regulator pins30, 3|. The secondary coil 52 of the transformer may have a greaternumber of turns than the primary, and in practice it has been found thatby use of a battery 50 having a potential of 1 volts, a potential ashigh as 1500 or 2000 volts may be developed at the terminalsof thesecondary winding 52.

In some cases it has been found advanta eous to employ beryllium-copperhairsprings 23, 2?

and any sparking efiects can be reduced by the The sheet 42 can then be4 presence of a rhodium plating upon the hairspring. The regulator pins30, 3| can be made of palladium or of platinum-iridium, with a likeadvantage of avoiding electrical troubles.

The operation of the device is as follows:

The watch movement operates in normal fashion. That is, the power fromthe mainspring is delivered through the normal train to the escapewheel, and this escape wheel is being detained by the allet pins in theusual fashion. As the balance wheel 2| oscillates at a rate determinedby the mass of the balance system and the elasticity effect in thehairspring 25, the roller pin 23 of the balance system enters the forkof the pallet, in usual fashion, and causes an oscillation of thispallet. As usual, a clockwise movement of the balance will causemovement of the pallet in one direction, with a corresponding movementof the escape wheel: while the counterclockwise return stroke of theescape system effects the further release of the escape wheel by the oneunit of movement, through the action of On each occasion that the palletmoves to unlock and thereby permit movement of the escape wheel, theescape wheel also acts through the pallet to give impulse to the balancesystem to maintain the motion thereof. All this is old and well-known,and is described herein as indicating that the balance system is kept inmaintained oscillation at a predetermined rate. At each oscillation, thehairspring 25 tends to increase in the relative radius of each of itsturns during motion in one direction, and to decrease in such radiusduring motion in the opposite direction, with respect to the positionoccupied by the hairspring spiral when the system is at rest. As thehairspring expands (Figure 2) the over-coil portion 21 of the hairspringlikewise increases in relative radius, so that this part of thehairspring encounters the outermost regulator pin 3|. During the freemovement of the over-coil portion 2'! between the regulator pins, atentative circuit has been established from the battery extending on theone hand by conductor 40, with its pig-tail, the regulator arm 33 whichis insulated from the rest of the watch movement, and the regulator pins33, 3!. On the other hand, the battery 50 is connected through theprimary winding5| of the transformer and the conductor 41 to the balancecock l5, the hairspring stud 28, the over-coil portion 21 of thehairspring, but gaps exist between this over-coil portion 31 and theregulator pins 33, 3| so that no current flows. However, when theover-coil portion 2? encounters the regulator pin 3|, the circuit isclosed and current flows through the primary winding 5| of thetransformer, so that the field strength thereof is built up. As thismagnetic field strength varies, correspondingly a current flow begins inthe secondary winding 52 with a voltage across the terminals of thesecondary winding 52 which is roughly proportional to the turns-ratio inthe transformer multiplied by the voltage of the battery 50.

It will be noted that this encounter of the over-coil 2'5 with theregulator pin 3| is a normal procedure in the operation of the watchmovement. It occurs near the end of the particular stroke of oscillationof the balance system and I stroke, the energy stored in the hairspringcauses the balance to accelerate in the return stroke, wherewith theover-coil portion 2'? soon moves away from the regulator pin 3!,therewith opening the circuit again. Since the energization in thetransformer core is no longer being maintained, its magnetic fielddrops, and therewith a new current efiect is established in thesecondary winding 52, in the opposite direction.

The balance system accelerates until it reaches neutral axis, andtherewith the hair- 'spring 26 attains its spiral position of rest: butthe momentum of the balance wheel 2i now causes the system to continuein its movement past the'neutral axis, therewith again storing energy inthe hairspring 28., but causing a decrease in the relative radius of theturns of this hairspring. As the balance system slows down, near the endof this return stroke, the over-coil portion 2? now encounters the otherregulator pin 30, and again makes the circuit as before. When thisreturn stroke is completed, and the balance system again begins to movein the forward stroke, the circuit is again interrupted between theover-coil portion 2! and the regulator pin 39. It i will be noted thatthe time duration of closure of circuit between the over-coil portion 2?and the regulator pin 39 can here also be adjusted by bending theregulator pin 30, as indicated in Figure 2. It will be understood thatFigure 2, for clearness, has shown the relative spacing of the regulatorpins 33, SI, and the relative thickness of the over-coil portion 2% ofthe hairspring as greatly exaggerated.

Thus, in this illustrative form where both regulator pins 3d, 3! areelectrically connected to the ear 32 and conductor 46, the circuit forenergizing the core of the transformer til, 52 is energized twice duringeach oscillation of the balance system, once during the forward strokeand once during the return stroke.

While the normal hairspring length and section can be employed, this isnot compulsory: and it is feasible to use shorter hairsprings, orhairsprings of a different section, e. g. not normal for the specificwatch movement size; so that, for example, the balance system will havea lo-beat movement instead of a 5-beat movement per secend.

In Figure 4, the pillar plate It and the balance cock I50; support partsas described for Figure 2 except that the regulator lever 50 is of usualconstruction, as indicated in Figure 5, with the index arm 6! and thecar 62 for supporting the regulator pins 3%, 3%. The pallet or escapepiece 2t, with its fork, is shown in Figures l and '6 as supported bybearings 53, 64 carried respectively by the pillar plate l9 and by thepallet bridge 55 supported as usual from the pillar plate ID. The

pallet carries the sapphire pallet stones 6% for engaging the escapewheel 61. vAs the sapphire is non-conductive, there is no transmissionof electric current directly between the pallet and the escape wheel,and hence no spurious current changes at unlocking, drop, etc.

In this form, the balance cook is insulated from the pillar plate iii.The steady pins i5s are of insulating material, e. g. of nylon. As shownin Figure 5, the balance cock i5 is secured to the pillar plate by ascrew in which is illustrated as the electrical circuit, so that thecurrent having its head extending above the balance cock, andelectrically engaged with the conductor 47. Beneath this conductor, asit surrounds the screw ID, .is a disk H of insulating material, such asa plastic: cellophane has been found satisfactory for most employments.Beneath this disk H is an eye formed at the end of another conductor 46,this conductor thus being in electrical contact with the balance cocki5. An insulating sleeve '12 shown in dotted lines in Figure 5,insulates the screw 10 from the balance cock l5 along the length of thescrew. The threaded lower end of the screw engages in and forms bothmechanical and electrical connection to the pillar plate hi. A layer ofinsulating material 14, such as cellophane, is interposed between thebalance cock i5 and the pillar plate l0. Thus, the balance cock and itsstructures, including the regulator pins 36, 35 is insulated from thepillar plate it. When the watch parts used are of limited size andtolerance, the balance cock can be dressed on by an amount correspondingto the thickness of the insulating layer it.

The operation of this system comprises the normal operation of the watchmovement as described above. When the over-coil portion 27 of thehairspring is free of the regulator pins 30, 3 I, the current passagecan be from the battery by the conductor to to the balance cock l5, stud23, the hairspring 2?, 26, collet 25, the staff 26, and roller 22 to themetal roller pin 23: but this circuit is only completed at the rollerpin 23, when this roller pin is in contact with one or another part ofthe pallet 2s. Thus, as the balance system approaches neutral axis inits forward movement, the metal roller pin 23 enters the roller notch onthe pallet 24 and makes contact with the far side of this notch,therewith producing mechanical movement of the pallet to unlock theescape wheel and at the same time completing can continue its flowthrough the pallet, the pallet staff, the metal bearings 53, B4, of thepallet arbor, the pallet bridge and the pillar plate I 0, screw iii, andconductor 4'! back through the primary winding 5! of the transformer tothe battery 50, using the same external circuit as shown in Figure 1.Thus, the core of the transformer is magnetically energized. Theunlocking of the escape wheel is, however, promptly followed by themovement of this wheel and its action upon the pallet todeliver impulseto the roller pin and thus to the balance system. Therewith, the palletis accelerated and moves faster than the roller pin, so that thiscircuit is opened again momentarily. When the pallet again strikes theroller pin, to deliver impulse, the circuit is again closed. Finally,since the pallet and the roller are moving about different axes, theyagain separate in the usual movement of the watch structures, and thecircuit is opened again. During the return stroke of oscillation of thebalance system, likewise, two circuit closures occur, the first-takingplace'when the roller pin encounters the pallet and causes unlocking ofthe escape wheel, and the second closure taking place when the pallethas accelerated and delivers the impulse to the balance system.

By the use of conductive bearings, such as metal bearing pieces 63, E34,for the pallet arbor, the current path is direct to the pillar plate l0and the pallet bridge 55, without requiring transfer into the gearsystem: and by having the pallet stones 66 of sapphire, actualinsulation is provided, so that the opening and closing of theelectrical circuit is not a function of the unlocking or impulsingbetween the escape wheel and the pallet.

The structure shown-in Figures 4, 5, and 6, and employing sapphirebearings for the balance staff '20, is of use and value where arelatively high resistance in the primary circuit is permissible ordesirable. In this arrangement, the current flows through the entirelength of the hairspring between the stud 28 or the regulator pins 30,3| and the collet 25.

Where the employment of such a high resistance is not desirable orpermissible, a modified form .of construction can be used, which isessentially identical in general appearance with that shown in Figures4, 5 and 6, but in which the bearing stones I'I, I9 are of conductivematerial, such as metal. The operation, in this case, involves thenormal movement of a watch structure as described above, but in thiscase the current flows from the balance cock I5 through the conductivebearing pieces I'I, I9 directly to the staff 20.

. "When a pulse of extremely short duration is required, this can beattained with the same general structure, but with the banking pinsinsulated relative to the frame: that is, as in Figure 7, the sub-plate80 is separated from the main frame by bonding insulation 8i andsupports the metal banking pins 82, the circuit then leading from thesub-plate 80 by conductor I0. In this case, the contact of theconductive roller pin 23 with the pallet 24 closes the, circuit throughthe pallet and the banking pin 82 then in contact with the pallet, andthence by conductor Iii. as before. The mechanical action of the rollerpin upon the pallet, however, immediately separates the pallet from thebanking pin, and the circuit is thus quickly and immediately brokenagain. As the pallet moves, it over-speeds theroller pin,

and comes to rest against the other banking pin without re-making thecircuit. When both banking pins are conductive, such rapidly succeedingmake-brake actions occur in both strokes.

The higher resistance path, through the hair- ,spring 26, 21 exists asbefore, but is in parallel to the main low resistance path through thebearings I'I, I9, and is not dominant in the action.

The operation of the devices, as described above, produces single beatsor double beats per stroke of the balance system, and these beats appearas electrical impulses of predeterminable length and frequency. Anotherfeasibility of employment of the system is that of providing amechanical interrupter of small size and weight but capable of deliveryof calibrated quantities and voltages of current. Such an employment isindicated in Figure 1, in which the secondary or output winding 52 isconnected to the four rectifiers I00, Il, I02, I03 arranged in bridgefor double-wave rectification of the alternating impulses from thewinding 52, and so directing these impulses that they build up aunidirecti onal potentia1 difference upon the condenser I ;connectedbetween the mid-points of the .pairs of rectifiers I0ii-I02 and IOIIfi3.These mid-points I06, I01, thus constitute terminal from which a steadyhigh potential direct current may be drawn. Such a current can thus beeasily and simply produced for use in an electrometer or like electricalpotential device. -:In practice, the device Will handle relatively highcurrent density at the contacts. In one example of practice with thestructure shown in r Figures 1, 2 and 3, the current densityv duringelectrical flow, in the fraction of the hairspring inch.

It is obvious that the invention is not limited to the forms ofconstruction shown, but that it may be employed in many ways within thescope of the appended claims.

We claim:

1. A chronometric circuit controller including a chronometric movementhaving a frame and thereon a balance assembly of staff, wheel, andhairspring and a pallet, the combination therewith of a regulator leverelectrically insulated from the frame and carrying a conductiveregulator pin for engagement by the hairspring during balanceoscillation, and conductors electrically connected to the hairspring andto said regulator lever.

2. A chronometric circuit controller as in claim 1, in which the saidregulatorlever is part of an assembly comprising a bearing portion, ancared portion, and an insulation layer mechanically connecting saidportions and insulating them from one another, the ear of said latterportion supporting the regulator pin.

3. A chronometric circuit controller as in claim 1, in which the saidregulator lever is movable for varying the position of the regulator pinrelative to the hairspring, whereby to change the duration of contact ofthe hairspring and regulator pin.

4. A chronometric circuit controller including a chronometric movementhaving a main frame piece and a balance cock piece, electricallyinsulating material separating said pieces, a balance wheel and staffmounted in said pieces for oscillation, a hairspring connected to thebalance wheel and staff at one end and to the balance cock at the otherend, a pallet pivoted on said main frame, a roller on said staff andhaving a conductive roller pin cooperative with said pallet, andconductor means leading from the balance cock and the pallet.

5. A chronometi'ic circuit controller as in claim 4, in which the mainframe piece has an electrically conductive bearing for the pallet,forming part of the conductor means from the pallet.

6. A chronometric circuit controller as in claim 5, in which the pallethas insulating pallet stones.

'7. A chronometric circuit controller, including a chronometric movementhaving a frame and thereon a balance assembly of staff, wheel, andhairspring and a pallet, said balance staff being electrically connectedto the frame, the combination therewith of an electrically conductivebanking pin electrically insulated from the frame, said pallet being ofelectrically conductive material and electrically insulated from theframe, and a roller of electrically conductive material carried by saidbalance staff and having thereon a conductive part cooperative with thepallet during the oscillation of the balance assembly, and conductorsleading from the frame andirom the said pin.

8. A chronometric circuit controller, including a chronometric movementhaving a frame and a balanced assembly including a balance staff, saidbalance staii being electrically connected to the frame, a conductiveelement carried in oscillation by said staii, a contact member mountedon the frame and presenting a part in the path of oscillation movementof the said conductive element to be contacted electrically and movedmechanically thereby, a conductive element insulatedly mounted on theframe and positioned in the path of movement of said contact member, andelectrical conductors leading from said conductive elements whereby thecircuit through said conductors is closed only during the period whensaid contact member is simultaneously engaged with both said conductiveelements.

9. A chronometric circuit controller including a chronometric movementhaving a frame and a balance assembly including a balance staff, acontacting element carried in oscillation by said staff, a conductivecontact member mounted on the frame and presenting a part in the path ofoscillation movement of the said contacting element and movedmechanically thereby, a conductive element insulatedly mounted on theframe and positioned in the path of movement of said conductive member,and electrical conductors leading from the said conductive element andconductive contact member whereby the circuit through said conductors isclosed only during the period when said conductive contact member issimultaneously engaged with both said contacting element and saidconductive element.

10. A chronometric circuit controller including a chronometric movementhaving a frame and a balance assembly including a balance staff, saidbalance staff being electrically connected to the frame, a conductiveelement carried in oscillation 10 by said staff, a contact membermounted on the frame and insulated from the frame and presenting a partin the path of oscillation movement of said conductive element to becontacted electrically and move mechanically thereby, a secondconductive element insulatedly mounted on the frame and positioned inthe path of movement of said contact member, and electricalconductors-leading from said conductive elements whereby the circuitthrough said conductors is closed only during the period when saidcontact member is simultaneously engaged with both said conductiveelements.

